The present invention relates to an image forming after-treatment apparatus for performing an after-treatment such as a stapling processing with respect to some sheets of recording paper discharged from an image forming device such as a copying machine, a printer, etc.
A conventional image forming after-treatment apparatus is disclosed in Japanese Laid-Open Patent Nos. 62-20046, 62-191375, 62-176246, 62-290669, 59-82263 and 63-101268, etc., for example. In accordance with the construction of such an image forming after-treatment apparatus, as is generally well known, some sheets of recording paper sent out of the image forming device are stored onto a staple tray and are stapled and the stapled sheets of recording paper drop onto a tray arranged downwards and are then discharged.
In such a conventional image forming after-treatment apparatus, the staple tray located upwards obstructs an operation for taking the after-treated sheets of recording paper out of the apparatus. Further, an operator cannot take the sheets of recording paper out of the apparatus unless the operator bends his waist, which is painful for the operator.
Further, in the above-mentioned conventional apparatus, when the after-treatment is performed, it is necessary to align the sheets of recording paper with each other in one place. When the recording paper is stored onto the tray with an end face thereof as a reference, a fence is disposed in a position separated by a predetermined distance from the reference position, and the stapling operation is then performed by a fixed stapling device after the paper is moved and aligned. On the other hand, when the recording paper is stored onto the tray with a center thereof as a reference, jogger fences are reciprocated to align the paper from both sides of this center. Thus, the recording paper is supported by both jogger fences therebetween and is moved to the stapling device fixed in position to perform the stapling operation. In such a conventional apparatus, after the alignment of the sheets of recording paper, it is necessary to move the sheets of recording paper, thereby wasting the time for performing the stapling operation. Further, in another conventional apparatus, the jogger fences are reciprocated to align the recording paper in this center from both sides thereof, and the stapling device is moved to the aligning position to perform the stapling operation. However, in such an apparatus, it takes time to move the stapling device. Further, in another conventional apparatus, a reference fence and the stapling device are fixed in positions separated by a predetermined distance from a maximum size of the paper so that the recording paper hits against the reference fence and is aligned and stapled irrespective of the size of the paper. However, in such a conventional apparatus, when the size of the paper is small, the moving amount of the recording paper is large so that it is difficult to sufficiently move and draw the recording paper to the reference fence.